Mar 032013

Many NAT firewalls or VPN server time out idle sessions after a certain period of time to keep their trunks clean. Sometimes the interval between session drops is 24 hours, but on many commodity firewalls, connections are killed after as little as 300 seconds, and this can be a problem if you are working on a remote machine and suddenly you find yourself logged out with a message “Connection reset by peer”.

In a former article I’ve presented autossh, a solution that comes to your help when you want to be sure that a SSH connection stay always on between 2 machines. Autossh is a simple program that allows you to run an instance of ssh, keep it under control, and restart the same instance once that the connection is dropped up to a maximum number of times controlled by an environment variable.

This is useful if you need to have a “permanent” connection between 2 machines, but perhaps you just need to have a connection between your personal computer and different servers, and in these cases autossh is less useful, so let’s see how to use some openssh options to keep our connection open.
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Nov 212011

Article by already published on their useful  wiki (in Italian)

There are many occasions where you need to create connections to machines and services that are protected by firewalls because it is appropriate to adequately protect them, but for which the creation of a VPN becomes an excessive burden.

For this reason, the ability to port forwarding via SSH is very useful for creating an encrypted tunnel from one machine to another, allowing you to enable only local access (such as a MySQL only listens locally) safely, with the only the problem that in case of problems, the SSH connection (and its tunnels) could fall.

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Nov 022011

Article by Jimmy, first published on his Blog and the BGLUG in Italian

Gnucash  is a great tool to keep the budget of the family, and from the version 2.4.0 supports connection to a database, SQLite, MySQL or PostgreSQL for data storage. Using a local database, however, tie to a specific computer for its use. Instead I want to be able to open a GnuCash session from any computer and connect to a single, remote, database.

Enable remote connections to the database from the whole net is very unsafe, but a SSH tunnel gives me a lightweight and reliable alternative . Continue reading »

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3 easy steps to strengthen your ssh server

Back on ssh topic, i think this is third or perhaps the fourth article regarding ssh, one of my favorite tools on a Linux server, and that a lot of times is not used or configured properly. In this small guide i’ll show you some setup to make your ssh server a bit more safer [...]

More SSH Port Forwarding

Today I present another excellent article by Domenico Raffaele originally presented in his blog (in Italian) where you can find many other interesting articles about hacks and VoIP. This is his second article about ssh. Here you’ll see some example of SSH Port Forwarding, sometimes called SSH Tunneling, which allows you to establish a secure SSH [...]